After further testing with the web interface on the Mac I've come to the following conclusions:
In order for local connectivity to work your web browser must be allowed to listen for connections.
You can verify the firewall settings by going to the System Preferences, click on Security and going to the Firewall tab.
You have the following options to allow local network streaming with the sling feature:
a) Turn the firewall off entirely. If you're behind some other sort of firewall or using a non-routable addresses, this may be fairly safe and easy thing to do. This will allow the local streaming to work for any browser.
b) Specifically add your browser to the list of applications that are set to Allow incoming connections. Click the Advanced button in the lower right corner of the firewall config. Click the + button under the list of applications and choose your browser. Verify that your browser appears in the list with a green dot next to it and says Allow incoming connections. This will work for any browser you do this for. This makes me somewhat nervous doing this for an entire browser.
c) If you're using Safari you can use the "Automatically allow signed software..." feature. Safari is signed and checking this box is sufficient to make Safari accept the connection from your 922. This will not work for Firefox as Firefox is not properly signed to support this. I'm more comfortable with this configuration simply because I believe this option is checked by default.
If you're going to use Safari on Snow Leopard you must force it to run in 32-bit mode (the web interface will tell you if you need to do this). You can do this by following the directions here: Sling Media Support - Configuring Safari in Mac OS X 10.6 (Snow Leopard) to work with Slingbox.com
I've actually had a great deal of luck getting local streaming working with Safari on my Mac. The only real issue I've been having with it is that when clicking Dish Remote Access link on dishnetwork.com the browser hangs up and sometimes I have to hit the back button a couple times to get it to finally take me through to the sling.com site.
Hope this information is helpful to those of you out there that are having issues. I unfortunately don't have a Windows machine setup to give as detailed information on what you need to do over there.
In order for local connectivity to work your web browser must be allowed to listen for connections.
You can verify the firewall settings by going to the System Preferences, click on Security and going to the Firewall tab.
You have the following options to allow local network streaming with the sling feature:
a) Turn the firewall off entirely. If you're behind some other sort of firewall or using a non-routable addresses, this may be fairly safe and easy thing to do. This will allow the local streaming to work for any browser.
b) Specifically add your browser to the list of applications that are set to Allow incoming connections. Click the Advanced button in the lower right corner of the firewall config. Click the + button under the list of applications and choose your browser. Verify that your browser appears in the list with a green dot next to it and says Allow incoming connections. This will work for any browser you do this for. This makes me somewhat nervous doing this for an entire browser.
c) If you're using Safari you can use the "Automatically allow signed software..." feature. Safari is signed and checking this box is sufficient to make Safari accept the connection from your 922. This will not work for Firefox as Firefox is not properly signed to support this. I'm more comfortable with this configuration simply because I believe this option is checked by default.
If you're going to use Safari on Snow Leopard you must force it to run in 32-bit mode (the web interface will tell you if you need to do this). You can do this by following the directions here: Sling Media Support - Configuring Safari in Mac OS X 10.6 (Snow Leopard) to work with Slingbox.com
I've actually had a great deal of luck getting local streaming working with Safari on my Mac. The only real issue I've been having with it is that when clicking Dish Remote Access link on dishnetwork.com the browser hangs up and sometimes I have to hit the back button a couple times to get it to finally take me through to the sling.com site.
Hope this information is helpful to those of you out there that are having issues. I unfortunately don't have a Windows machine setup to give as detailed information on what you need to do over there.